Joby S4 Featured Image

Joby Aviation
Santa Cruz, California, USA

The Joby Aviation S4 is a four-seat electric Vertical Take-Off and Landing Vehicle using six vector thrust propellers on fixed wings and stabilizers.

Joby Aviation has been relatively secret with its S4 aircraft. It is believed to be a continuation of the Joby S2 design. Some few computer images of the S4 presented at the 2nd Annual AHS Transformative Vertical Flight Workshop held at the NASA Ames Research Center in July 2016. At the 2019 Vertical Flight Society’s sixth annual eVTOL Symposium Joby revealed additional information and initial performance details of test flights of scale and full sized demonstrators.

The S4 is configured with six tilting and folding blade propellers, four of which project forward from pylons on a 35-ft. (10.7) span high-wing and two that cantilever forward from a V-tail. A Distributed Electric Propulsion System (leveraged by NASA’s LEAPTech demonstrations) are powered by lithium-nickel-cobalt-manganese-oxide batteries, provides a range of 150 miles (241 km). The vehicle employs a unified flight control system to reduce pilot workload during the conversion to and from VTOL to horizontal flight mode.

In a demonstration for Bloomberg News, the S4 completed a piloted test flight that included a vertical takeoff, 15 minutes of flight along a 15 mile (24.1 km) course, and a controlled landing.”

Joby was honored in May 2018 with the Vertical Flight Society’s Paul E. Haueter Award, given for an outstanding technical contribution to the field of VTOL aircraft development other than a helicopter or an operational vertical flight aircraft was awarded to JoeBen Bevirt, the founder and chief executive officer of Joby Aviation Inc., for successfully demonstrating the world’s first high-speed multi-passenger electric VTOL aircraft.

According to the FAA Aircraft Registry, the aircraft has the registration N541JA, and the model number is JAS4-101 and the serial number is JAS4-1 (Joby Aircraft S4, aircraft number 1). The test vehicle is named Rachel.

Joby was initially funded by JoeBen Bevirt, Paul Sciarra and others. Series A and Series B investments have now reached $130M. In January of 2017, Joby Aviation received $970,000 from the Defense Innovation Unit Experimental (DIUx), a Pentagon organization that focuses on implementing cutting-edge technology into the U.S. Military. Joby’s efforts are backed by at least five large investors (Capricorn Investment Group, Intel Capital, JetBlue Technology Ventures, and Toyota AI Ventures).

At the VFS 6th Annual Electric VTOL Symposium on Jan. 29, 2019, Joby noted that the company had “Successfully flown subscale and full scale demonstrators” and provided the following details on the S4:

  • Safety assurance in EXCESS of CS-23 cert requirements
  • Unified flight control – extremely simple vehicle operations (SVO)
  • All electric CTOL/VTOL
  • 200 mph cruise
  • 150 mile range
  • 100x quieter than a helicopter

Joby Aviation is also working on a five-seat version (perhaps referred to as the “S5”) which, according to the company, will be “faster than existing rotorcraft, fly at least 150 miles on a charge, and be 100 times quieter than conventional aircraft during takeoff and landing, and near-silent in flyover.”

Joby S4 CFD (from the 2nd Annual AHS Transformative Vertical Flight Workshop, Aug. 2015)
Joby S4 CFD
Joby S4 top view
Comparison of Joby S2 and S4 with the R22 and R44 (from the 2nd Annual AHS Transformative Vertical Flight Workshop, Aug. 2015)
Comparison of Joby S2 and S4 with the Robinson R22 and R44


First Flight Early 2017
Capacity 4 Passengers
Propulsor 6 Folding Propellers
Power Lithium-nickel-cobalt-manganese-oxide batteries
Range 150 miles (246.4 km)
Wingspan 35 ft (10.7 m)
Length 24 ft (7.3 m)
Weight 4,000 lb (1,815 kg)
Max Speed over 140 mph (225.3 km)

Primary Takeoff and Landing Location:





JobyVectored ThrustFlight Testing,  4 PassengersElectric/Batteries, PilotedVFS Member